<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.7.14/dist/vue.js"></script>
</head>
<body>
    <div id="app">
        
            <input v-model="newmess">
            <button @click="add()">添加</button>
        </div>
    </div>
    <ul>
        <li v-for="(v) in arr">
        <div v-if="!arr.edit">
            {{ arr.text }}
          </div>
        </li>
    </ul>
    <script>
        let vm=new Vue({
            el:'#app',
            data:{
                arr:[],
                newmess:''
            },
            methods:{
                add(i){
                    this.arr.push=({id:i},{text:this.newmess},{edit:1})
                    this.newmess=''
                }
            }
        })
    </script>
</body>
</html>